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Scott Blanchard is President and CEO of Vaunix, the creator of Lab Brick™ Signal Generators, Digital Attenuators and commercial hubs. We asked Blanchard his perspective on the emerging market of USB powered test equipment.

MWJ: Does USB test equipment compete with other established ATE platforms such as LXI/PXI?

SB: The low cost and simplicity of USB products are attractive features for ATE engineers. Since PCs and laptops are already “USB compatible” and equipped with multiple USB ports, users are not required to purchase controllers, interfaces, racks or cabinets. The required operational software is almost always included with the USB equipment purchase. This often includes software development kits (SDK) and drivers for many common programming languages and platforms. Given the cost advantages, the ease of use and familiarity of USB along with its flexibility, USB-based ATE is a very attractive alternative.

MWJ: How has the economic environment influenced the adoption of USB based test equipment?

SB: Over the past decade the vast majority of companies have reduced, or at best maintained their capital expenditure budgets. This change is forcing engineers and production managers to do more with less. As a result, customers are looking for lower cost equipment that is easy to use and gets the job done. USB test equipment is proving to be an excellent fit for these customers. By connecting the USB equipment to a computer, the user can access a virtual front panel thus eliminating the need to build the display cost into the instrument. This same interface also supplies the DC power thus eliminating costly AC/DC power conversions and further clutter from the test stands.

MWJ: USB power is often perceived as “dirty”. Does this cause a problem for USB enabled devices?

SB: The voltage supplied by the USB connection is very dependent upon the quality of the controlling PC or hub. There is no doubt that there are some poor quality PCs and hubs on the market. Proper line conditioning can all but eliminate the issues caused by USB voltage. The ability to withstand the variations in quality of voltage stability and supply noise is often what differentiates USB equipment suppliers. In our Lab Brick products we are extremely careful to internally regulate and condition the voltages used throughout each unit. As a result, even the phase noise performance of our most sensitive 20 GHz signal generators are completely unaffected by voltage variations and noise spikes.

MWJ: How do you combat the perception of USB products as being “cheap”?

SB: Historically, commercial USB products such as thumb drives, MP3 players and even hubs have been built in flimsy plastic housings that are often considered unreliable and disposable. The reality is that there is a vast difference between commercial grade products and the industrial strength USB products such as our Lab Brick line of equipment. At Vaunix, we build all of our products in cast aluminum housings with board lock connectors to remove this false perception. The quality and reliability of USB based test equipment is as good as the company producing the products.

MWJ: What feature has driven the growth and adoption of the USB powered test equipment market?

SB: There are really two main reasons for the growth in the USB equipment market. The first reason is the lower cost structure involved with the USB interface as discussed earlier. The second reason for the growth in the market is portability. The small size and weight of USB powered test equipment is perfect for field engineers, on-site support engineers and even application engineers. As an example, our Lab Brick digital attenuators and signal generators weigh less than a pound each. Our customers find it very convenient to carry a laptop and a Lab Brick when working at remote antenna test ranges, radar sites or demonstrating hardware to their customers.

MWJ: Many corporations are intent upon reducing their carbon footprint. Can USB test equipment, and more specifically Lab Brick products help with this green initiative?

SB: Although commercial USB products themselves are not “Green”, USB powered test equipment, such as our Lab Brick product line, use far less energy than conventional bench top lab equipment. USB products are limited to 2.5 W of power per connection. As a result the Lab Brick LMS-103 signal generator running at 10 GHz with pulse modulation enabled uses the full 2.5 W available. By comparison, a conventional bench top signal generator generally consumes between 65 and 100 W of power. When the USB equipment is incorporated into ATE racks, the improved power consumption reduces the amount of heat produced. This reduces and in some cases even eliminates the need for forced cooling which further improves overall energy efficiency and ultimately test stand reliability